Comparative evaluation of water sorption and solubility of two autopolymerizing soft denture liners in distilled water and artificial saliva

Abstract

Statement of the Problem: Sorption and solubility by soft liners is accompanied by volumetric changes, microbial infestation, distortion, hardening, color change, and reduced bond strength between the liner and denture base. Water sorption and solubility of soft liners are, therefore, of obvious importance because of their influence on the long-term stability of a soft liner. Aim: The purpose of this study was to evaluate and compare the water sorption and solubility of two chemically distinct soft liners (acrylic-based soft liner, Viscogel and silicone-based soft liner, Mollosil) at different storage intervals over 3-month period. Methods: Sixty disc-shaped specimens (30 mm × 1 mm) of each liner were fabricated, weighed, and divided into six groups of ten specimens each. The specimens were immersed in distilled water and in artificial saliva, and their weight data following immersion and subsequent drying were collected at 1 week, 1 month, and 3 months. The percentage sorption and solubility were calculated, and the data were submitted to one-way analysis of variance (ANOVA). The means were compared using Tukey's honest significant difference post hoc comparison. Results: One-way ANOVA revealed significant difference in the sorption and solubility between the two materials. Acrylic-based soft liner, Viscogel, demonstrated higher percentage absorption and solubility than its silicone-based counterpart, Mollosil, at all-time intervals in both distilled water and artificial saliva. Conclusion: On the basis of lower water sorption and solubility, silicone-based soft liner, Mollosil, may provide for better clinical success than acrylic-based soft liner, Viscogel.